Never apologize for or otherwise undercut the argument you've made or leave your readers with the sense that "this is just little ol' me talking." Leave your readers with the sense that they've been in the company of someone who knows what he or she is doing. Also, if you promised in the introduction that you were going to cover four points and you covered only two (because you couldn't find enough information or you took too long with the first two or you got tired), don't try to cram those last two points into your final paragraph. The "rush job" will be all too apparent. Instead, revise your introduction or take the time to do justice to these other points.
After becoming a teacher it became pretty clear that no one outside of education can understand just how brutal and time-consuming it is to be a teacher — especially when it comes to grading essays. But on the flip-side most teachers don't know how or where technology can help them. Or worse, they're surrounded by all this awful technology that's been forced upon them. My district's attendance system required three separate logins! Three! Argghh! Last year I had four sections of the same Senior English prep. That meant 96 papers would come in all at once. I was super-passionate about getting these regular-level students ready for the rigors of college so I would find myself spending 15, 20, 30 minutes per paper. That multiplied by 96 is insane. That's where came from — as a teacher I felt the same pain you're feeling but my programming background allowed me to see where a little bit of technology could go a long way.